title: Assessment of the acute toxicity of the organochlorine pesticide endosulfan in Cichlasoma dimerus (Teleostei, Perciformes).
abstract: The organochlorine insecticide endosulfan (ES) is widely used despite its high toxicity to fish (96-h LC(50) median value of 2.6 μg L(-1)). This study aimed to assess the acute toxicity, histological and physiological parameters after exposure to 0; 0.25; 1; 2; 3; 4 and 16 μg L(-1) ES for 96 h under semi-static conditions in a freshwater perciform fish, Cichlasoma dimerus. Prior to death, fish exhibited behavior indicative of neurotoxicity. No difference was found in brain AChE activity. A decrease in erythrocyte mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration in exposed fish suggests a state of anemia. Histological alterations observed in exposed fish included hyperplasia of the interlamellar epithelium, blood congestion in secondary lamellae, and mucous cells hyperplasia and hypertrophy in gills; pycnotic nuclei and hydropic degeneration in liver; testicular damage. These moderate pathological responses in major organs could become crucial during reproduction and under prolonged exposure periods.
authors.affiliation: Laboratorio de Ecotoxicología Acuática, Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, C1428EHA, Argentina.
authors.forename: Rodrigo Hernán
authors.initials: RH
authors.lastname: Da Cuña
authors.forename: Graciela
authors.initials: G
authors.lastname: Rey Vázquez
authors.forename: María Natalia
authors.initials: MN
authors.lastname: Piol
authors.forename: Noemí Verrengia
authors.initials: NV
authors.lastname: Guerrero
authors.forename: María Cristina
authors.initials: MC
authors.lastname: Maggese
authors.forename: Fabiana Laura
authors.initials: FL
authors.lastname: Lo Nostro
mesh_terms: D000818:Animals; D023681:Cichlids / Q000502:physiology*; D004726:Endosulfan / Q000633:toxicity*; D005260:Female; D005618:Fresh Water / Q000737:chemistry; D005880:Gills / Q000187:drug effects / Q000473:pathology; D022781:Hepatocytes / Q000187:drug effects; D006843:Hydrocarbons, Chlorinated / Q000633:toxicity; D007306:Insecticides / Q000633:toxicity*; D007928:Lethal Dose 50; D008099:Liver / Q000187:drug effects / Q000473:pathology; D008297:Male; D010053:Ovary / Q000187:drug effects / Q000473:pathology; D013154:Spleen / Q000187:drug effects; D013737:Testis / Q000187:drug effects / Q000473:pathology; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D006843:Hydrocarbons, Chlorinated; D007306:Insecticides; D014874:Water Pollutants, Chemical; D004726:Endosulfan